A dental implant is an artificial prosthesis normally comprised of a single cylindrical component to replace the missing root structure of a natural tooth that has been lost. This single stage is inserted into a prepared hollowed out site (osteotomy) in the patient's jawbone (endosseous) and typically remains buried there for a period of time to allow for “osseo-integration” or the growth and adhesion of natural bone around the implant “root screw”, securing it in place. This cylindrical implant typically contains down its internal center a machined threaded internal hollow sleeve that allows the dental practitioner upon later surgical exposure of the head or top section of the cylindrical implant to screw into place a machined screw-in abutment (either with an integral screw on its inferior aspect or a separate connector screw which threads through a center hollow sleeve of the abutment) or a transfer abutment screw that is modified and then sent to a dental laboratory for fabrication of the abutment. The head section of the implant is simply the top segment of the cylindrical implant form and is an integral part of it. The abutment (s), which extends into the oral cavity, is then utilized by the dentist to fabricate a single fixed prosthesis (crown), a multiple fixed prosthesis (dental bridges), or can take the form of a fixed prosthesis (over-denture bar prosthesis) to anchor a removable prosthesis such as a permanent denture, using techniques that are widely known in the dental field.
There are several major drawbacks to this standard implant design. These drawbacks are derived from the fact that the standard implant design form is actually in very significant variance to the natural root form of human teeth. There are different types of teeth in the humans, namely, the upper and lower incisors, canines (cuspids), premolars, and molars. These teeth differ to a significant degree in form from each other between the different categories, and they differ as well within each category depending on whether they are in the upper or lower jaws and which position they have in each jaw (a maxillary first molar is significantly different in form from a corresponding mandibular first molar and a maxillary second molar is different in form from a maxillary third molar). These differences in form apply not only to what is termed in dentistry as the crown portion of the teeth (the part of the tooth that is erupted into the mouth and visible to the eye) but extends as well to the forms of the root (s) portion (buried in the alveolar bone socket of the jaws) of these different categories of teeth in both the maxilla and mandible.
The distal aspects of the natural roots of teeth are basically cylindrical or somewhat oval in cross-section. When one though observes in cross-section the natural form of the roots of teeth at the level of the transition of the tooth from its root segment to its crown segment (this level is referred to in dentistry as the CEJ—cemento-enamel junction or the cervix of the tooth) one is immediately struck by the fact that in general most of the root forms in cross-section of the teeth are anything but cylindrical in shape or form (the standard dental implant form is cylindrical in cross-section along its entire length). Depending on the type of tooth in question, the natural root form of the teeth in cross-section are in fact very oval at this level (at the cervix), either in a horizontal axis in relation to the crestal bone ridge of the jaw when one is referring to incisors, or oval in a vertical axis in relation to the crestal ridge when one is referring to the premolars, and quite rhomboid, or kidney shaped when one is referring to the molars. The cross-sectional form at the level of the CEJ and particularly the dimensions of that form of each type of these natural teeth (incisors, cuspids, premolars, and molars) vary as well, depending on the jaw size and genetic variation of each individual patient. In addition, when one is referring to the molars, the natural teeth typically exhibit multiple roots (typically the molars are bi-rooted in the mandible and tri-rooted in the maxilla).
The standard dental implant design being cylindrical in form along its entire length including the head or top segment of the implant, and consisting of a very limited number of different sized single “root screw” cylinder takes none of the above-mentioned natural variation of the roots of the different types of teeth into account, both in the maxilla and the mandible.
Due to its cylindrical form along its entire length, the standard dental implant does not conform at the level of the crest of jawbone (Cervix or CEJ) to the natural oval, rhomboid or kidney-shape form of the roots of the natural teeth (the head of the implant is cylindrical in cross-section). This major discrepancy in the contour or emergence profile, as it is termed in dentistry, of the crown that is fixed upon the implant abutment (which fits into the head of the implant) in relation to the gums results in large gaps or spaces between the implant crown and the teeth on either side of it and prevents the optimal formation of the interdental papilla (gum tissue between the teeth). With the posterior implant, the situation is very much analogous to a large ball sitting on top of a thin stick. These large open areas or gaps allow for food debris, plaque, and pathogenic bacteria to accumulate between the implant crown and the natural teeth adjacent to it, making these areas very difficult for the patient to keep clean and requiring the patient to use special cleaning implements to try and maintain them free of food debris and plaque. In many cases this situation over the long-term results in poor health of the gums, causing periodontal (gum) disease of the adjacent teeth as well as documented cases of implant failure due to crestal bone resorbtion.
Additionally, as was previously mentioned, all standard implants on the market consist of a single cylindrical “root screw” form or stage that is buried into the alveolus (jawbone) to replace the natural root of the missing teeth. A second stage abutment is later screwed into the “root screw” (the abutment sits above the bone in the mouth) and a crown is made to sit on top of the abutment. This represents your typical standard two stage implant (the crown is never considered as a stage of the implant). Recently, one stage implants have been designed where the root screw stage and the abutment stage are all one integral piece. These are almost exclusively being used at present for the replacement of missing anterior teeth only.
This accords to a relatively good degree for the replacement of all the anterior teeth in the mouth but is not at all in accord with the natural state for replacing the posterior teeth, where as was previously mentioned, the upper molars are typically tri-rooted and the lower molars are typically bi-rooted.
The reason why providence formed these molar (posterior) teeth with multiple roots is that these teeth are designed to take on the entire burden of grinding and chewing most of the food we eat and they also are designed to maintain the proper vertical jaw relation between the upper and lower jaws, referred to in the dental field as the Vertical Dimension of Occlusion (V.D.O.C.), or maintaining the proper “bite”. Multiple rooted teeth versus single rooted teeth offer the advantages of spreading this intense load more efficiently as well as providing far greater stability from tipping or shifting the position of the teeth under load. They also provide vastly greater anchorage of these posterior teeth in their jawbone sockets as they engage a far greater surface area of bone buried in their multiple bone sockets. Because the load is distributed more efficiently, each singular root of these multi-rooted molars is individually thinner, shorter, and therefore smaller than would be the case if these teeth had instead been formed in the natural state with a longer, thicker and therefore larger single root buried in a single larger bone socket.
Standard implants with their single “root screw” design best tolerate compressive loading forces. Compressive forces are forces that are apically directed along the long axis of the implant. Tensile forces are forces that are coronally directed along the long axis of the implant and are not tolerated well by the implant. Shear forces are off-axis forces or loads on the implant that have the potential to be most destructive to the integrity of the implant-bone complex. Due to their single “root” design, standard implants placed in the molar (posterior) areas of the mouth are most susceptible to the negative effects of shear off-axis forces. Crater-shaped bone defects which are typically found clinically to form around the “heads” (top portion of the implant embedded in the bone) of these implants over time are suspected to be a result of such adverse loading. (G. Bergkvist, DDS. Dept. of Dental Materials Science, Malmo University, Sweden 2007).
Stress forces when an implant is “loaded” are known to be concentrated at the “head” or top part of the implant that is buried in the bone. The relatively narrow cross-sectional diameter of the single “head” of most dental implants does not allow for the proper distribution of this load for molar implants. Between 10-20% of the adult population are bruxers, people who habitually grind or clench their teeth to reduce stress (J. Oral Rehabilitation, 2008).
The average standard implant (two-stage) can take a vertical (compressive) loading force of 450 pounds per square inch or 32 kilos per square centimeter. The average bruxer generates a vertical (compressive) loading force of up to 600 pounds per square inch or 42 kilos per square centimeter, a figure well in excess of what the standard dental implant can comfortably handle over time. As noted above, vertical (compressive) loading forces are the forces best handled by standard dental implants, as opposed to shear (off-axis) loading forces which are much more damaging over the long term to the integrity and viability of the standard dental implants (and particularly standard posterior molar implants) in the mouth.
Splinting (connecting together) implants has been proven to reduce stress over unsplinted implants by a very large factor (Univ. of Malmo, Sweden 2007).
On an evolutionary level, the upper and lower jaws have adapted anatomically over a vast time period to the thinner, shorter and therefore smaller natural root form of the multi-rooted posterior molars by lightening the weight of the human skull and its considerable load on the spinal column in the following manner:
The upper jaw (maxilla) in the molar(s) region contain empty spaces called sinuses immediately above and in many cases actually wrapping around the tips of these multi-rooted teeth. In the lower jaw there is a marked sloping in or reduction in the width of the mandible on both the buccal (cheek-side) and lingual (tongue-side) of the bony plates from the crest of the jawbone to the inferior line of the mandible. Additionally, the inferior alveolar nerve runs in a canal in the mandible in an inferior position to the lower teeth.
All of the above presents significant challenges to the dental practitioner when attempting to replace these missing posterior teeth with the standard dental implant design. Due to their single large cylindrical “root” form, the anatomy of the upper and lower jaws can be particularly unsuitable to accommodate the standard dental implant design in these molar regions. This is because typically the standard posterior implant dimensions are 4.7 millimeters in cross-sectional diameter and 13 millimeters in overall length. These dimensions are necessary in order to place an implant of sufficient size that can reasonably handle some of the forces of the load placed upon it in the posterior upper and lower jaws.
This unsuitability of design is the case even more so in patients who have large maxillary sinuses in the upper jaw or crestal height resorbtion of the maxilla or mandible (a very common finding in patients who have previously lost their molars). These particular cases typically require additional surgical procedures such as maxillary sinus lifts (42% of maxillary posterior implants required sinus lifts in a retrospective seven year study published in the Journal of Periodontology, 2008) or maxillary and mandibular crestal ridge augmentation in order to make these sites better suited to accommodate the physical dimensions of the standard dental implant (provide sufficient depth of bone at the implant site so as not to puncture the sinus). These procedures are costly and are associated with concomitant health risks to the patient. Often these anatomical limitations may force the dentist to place the implants in a non-optimal location or if the limitations are severe, they may totally preclude the patient from receiving this restorative treatment option altogether.
The dentist also runs the general risk in many cases of perforating the maxillary sinus (compromising its health), perforating the lingual or buccal plates of the mandible (causing infection and implant failure), or disturbing or partially severing the inferior alveolar nerve in its canal in the mandible (causing a temporary or permanent parasthesia) when attempting to place a standard posterior dental implant.
Bone quality and volume are of paramount importance to the dental surgeon placing implants. It is important for the dentist to consider bone quality from a biomechanical standpoint. Generally, the anterior mandible has the densest bone followed by the posterior mandible and then the anterior maxilla, with the posterior maxilla being the least dense. Low density bone requires a longer healing period to maximize bony adaptation to the implant surfaces.
The upper and lower jaws are made up of a narrow strip of softer, spongy, alveolar bone sandwiched between two outer thin hard cortical plates of bone. In the posterior regions the entire width of the jawbones is typically 5 to 7 millimeters thick. The average interdental (between the teeth) space remaining when a molar tooth is lost is 10 to 12 millimeters long. The vertical depth of alveolar bone present where the tooth was lost can be as little as 5 to 10 millimeters before one encounters either the maxillary sinus space (in the upper jaw) and the inferior alveolar nerve (in the lower jaw).
Additionally, as was noted above, the loading force on these posterior teeth (molars) is much greater than the loading force placed on the anterior teeth. For this reason the diameter of the standard implant used to replace these missing teeth is significantly larger than the diameter of the implants used to replace missing anterior teeth.
To allow for a proper volume or thickness of jaw bone between the implant and the adjacent teeth so as to allow for a proper blood supply and health of the bone between the implant and the adjacent teeth, it has been accepted in the dental field to maintain a minimum distance of 2 millimeters between the implant and the adjacent teeth on either side of the implant. As noted above, this means that the head of the implant at the height of the crestal bone should not exceed a diameter of 6 to 8 millimeters in a mesio-distal dimension (the distance between the adjacent teeth where the missing tooth used to be), based on the formula: interdental space (space left by the missing tooth) minus 4 millimeters (2 millimeters on each side of the implant)=maximum diameter of implant head. In the particular case of the posterior teeth (molars) it is typically either 10−4=6, or 12−4=8. As mentioned above, the entire width of the jawbones is typically between 5 to 7 millimeters thick (referred to in the dental field as its Bucco-Lingual dimension) in the posterior area. This means that in order to stay within the confines of the jawbone and not puncture the outer cortical plates of the jawbone, the maximum dimension of the head of a standard implant which is round in cross-section should typically not exceed 6 millimeters in diameter.
In addition to the above space requirements and limitations, it is well known in the dental field that a minimum distance must be maintained between multiple implants as well (distance between one implant and the next when placing two implant next to each other) in order to maintain the proper bold supply to the bony tissue between the implants and prevent resorbtion or “die-back” of said bone.
Several systems have been developed to try and mitigate some of the significant drawbacks of the standard “single root” dental implant design described above. To better approximate the natural form of the root of the tooth at the cervical junction, an example of this is a one-piece dental implant as described in U.S. Pat. No. 6,854,972, February 2005, Elian, wherein a flaring cervical portion is incorporated in the proximal (coronal) end of the implant.
U.S. Pat. No. 6,093,023, July 2000, Meseguer, describes an implant with an “external” polygonal “head”. This is a confusion of terminology as what is being described is a polygonal abutment which is external (above the crestal height of the jawbones) to the endosseous implant. The actual “head” of the implant embedded in bone is round in cross-section (not polygonal), and an integral part of the “body” of the “root screw” component. This implant aims to provide a more anatomical shape for the abutment and a better esthetic result for the “peri-implant” (gums) soft tissue.
U.S. Pat. No. 7,291,013 November 2007, Aravena and Kumar, describes a standard single root form implant similar to U.S. Pat. No. 6,854,972, yet with a more pronounced anatomical flaring of its coronal segment or “head” as well as a more flared “abutment” component that closely matches the contour of the “head”. It still maintains a round cross-sectional form of the integral head of the “single-root” implant.
In an attempt to improve soft tissue attachment, U.S. Pat. No. 6,527,554 March 2003, Hurson and Dragoo, describes a roughened zone on the coronal head of a standard single-root form implant to better preserve the “biological width” or “attachment zone” between the implant-abutment interfaces.
U.S. Pat. No. US 2010/0003638, January 2010, Collins, Flynn, and Murray, describes a modular “single-root” implant design which includes a “head” an intermediate part which is porous in an attempt to better engage bone, and on its inferior aspect a short length threaded “screw” segment. While the intermediate (middle) section may possibly enhance bone adhesion over the long term, it does so at the expense of allowing for the initial “bite” into the osteotomy bore shaft and initial fixation of a standard “root screw” which features a threaded screw form down most if not all of its length.
In an attempt to provide for a multi-rooted tooth form implant, WO Pat. App. No. 2006/082610 August 2006, Cito, D'Ambrosio and Vinci, describes a “multiple-root” form dental implant design with a “head” component which it calls a “collar” and a “root screw” component which it calls a “fixture”. For the sake of clarity the terms “head” and “root screw” used by the present invention for these components will be used to describe these components in regards to this prior art.
This prior art is very limited in its design and incorporates as well significant structural defects that could compromise its short and long term viability in the mouth and could actually cause over time a catastrophic failure of the components of its separate stages as will be explained below. Additionally, the tools described in this prior art do not allow for the accurate, precise, and reproducible preparation of the implant site as well as the accurate, precise, and reproducible assembly of the components of the implant within that site in a three-dimensional manner.
This prior art describes a design wherein the “root screw” components are by necessity of smaller diameter or girth than the attachment (connector) holes of the “head” component as they need to be inserted through these holes and then via an extending circumferential lip on its superior aspect of greater circumference (which acts as a limiting stop) engages the smaller circumference of the insertion hole of the “head” component in order to relate these two components to each other.
This is a significant drawback in the structural design of the prior art for the following reasons: As noted above, there are significant limitations on the maximum interdental (mesio-distal distance between the teeth) and bucco-lingual (width of the jawbone) dimensions of the implant site. The diameter of the “head” component that can typically be accommodated in this limited implant site for missing molar teeth without puncturing this three-dimensional volume of the bone in both of the above two dimensions is itself quite limited. Therefore, the attachment (connector) holes contained within it must of necessity be of smaller diameter than the “head” which contains them.
By incorporating in its basic design a “root screw” that must of necessity be of smaller diameter than the retention hole of the “head” component into which it slides through requires the “root screw” component of this prior art to be extremely “thin”, resulting in a critically insufficient diameter or girth for these “root screw” components. As these “root screw” components are the primary structures of the implant that provide the retention, stability and load support for the entire implant, this design flaw is of critical importance and would jeopardize the long term and even short term viability of this implant design in the mouth (as noted above, it is accepted in the dental field to always use larger diameter single “root screws” for posterior implants compared to anterior implants due to the greater forces normally placed on the posterior implants). The inadequate diameter of these “root screws” is even more problematic when one considers the fact that all “root screw (s)” do not have a solid core and in fact must contain an internal hollow shaft to accommodate the connector screw which threads into it. This means that the thickness of the outer walls of the “root screw” design of this prior art must be extremely thin and would be very prone to fracture (resulting in complete failure of the implant) under even a minimal load.
Additionally, the very small diameter of the “root screw” components necessitated by the design of the prior art also necessitates that the single set of “connector screws” provided by the prior art to secure all three components (the “head”, “root screw” and abutment components) to each other to be even thinner than the “root screws” (as they must thread inside them), which, over time, (or even on initial load) could easily lead to their fracture under load. This would cause a separation of these two components within the jawbone, resulting in the complete failure of this implant design and a nightmare scenario for the dental practitioner to have to deal with.
Additionally, the abutment stage design of this prior art describes projecting tubes on the bottom surface of the abutment which extend through the retention holes in the head stage and the center shafts of the “root screw” stages in order to relate these components to each other. This design feature further limits the maximum possible diameter of the connector screws and also necessitates the further thinning of the outer walls (which contain the connector screw) of the “root screw” components. These design features even further increase the likelihood of the fracture and failure of these components, above and beyond what has already been noted, when these components would be placed under load in the posterior sections of the upper and lower jaws.
As mentioned above, the accepted protocol in the dental field is to allow for the endosseous (embedded in bone) elements of the implant to osseointergrate (solidify by allowing for the intimate bone adhesion to their surfaces during the healing process). This protocol of waiting for healing for several months duration is especially applicable to posterior (molar) implants due to the poor bone quality in these posterior regions of the jaws and the greater load these implants must support once they are placed under loading function (chewing on the crown atop their abutments).
In the prior art the “head” and two “root screw” components only passively connect to each other via a small self limiting flange or lip on the superior end of the “root screw” embodiment of the prior art at the time of the initial primary implant surgery procedure and are only secured to each other actively (with the single set of connector screws provided) after the entire healing period has elapsed and the dentist performs a small secondary surgery in order to gain access to the superior aspect of the “head” component so that he can secure the third abutment stage to the implant components that have already been embedded in the jawbone.
This means that during the extensive healing period, shifting is likely to occur between the “head” and two “root screw” components of the prior art (which are only passively connected to each other during this entire healing period) as the bone actively remodels around them and fixes these two components rigidly in their final position in the bone. This shifting and fixing in place of the shifted position of these components within the bone during healing may result, in the prior art, in a loss of parallelism of the “head” and “root screw” components of the prior art and therefore may not allow for the insertion of the two internal sleeves or tube features described on the inferior aspect of the abutment stage of the prior art into the corresponding two retention shafts of the “head” and “root screw” components. This would present an extreme problem for the dental practitioner to properly assemble the components of the prior art's implant and which might even necessitate the surgical removal of the implant, a highly undesirable result. If the shifting is minimal it still may require the dentist to use excessive force in order to screw down one or both of the connector screws through the now non-parallel shafts between these components. The forceful screwing of these two connector screws into the non-parallel shafts may compromise the integrity of the implant of this prior art, as it will place undue stress on the components and surrounding bone, and may result in bone resorbtion (die-back) and long term failure of the prior art's implant.
Drawbacks of the Surgical Tools: While WO Pat. App. No. 2006/082610 does describe a basic template guide for drilling the bore shafts to allow for the placement of the “root screw” components, its surgical template does not allow for preparing an accurate and precise depth and position of the bone preparation of the “head” component, and so does not allow for the accurate and precise insertion of these components in a reproducible fashion by the dental practitioner in the implant site.
This is due to the lack in this prior art of any form of clamping device to accurately and precisely fix the template over the implant site to allow for just such an accurate preparation of the bone at the implant site to receive both the “head” component and “root screw” components of the implant. As noted above, this is an absolutely critical requirement for any implant system to be successfully placed in an accurate and repeatable fashion in relation to the adjacent teeth or specific location in the jawbone deemed most advantageous by the dental practitioner for the insertion of the dental implant based on various diagnostic criteria known in the field. This prior art fails to achieve this basic requirement and so is impractical for the use of the dental practitioner who wishes to place implants with a high success rate.
It is important to note as well the method for preparing the osteotomy and inserting the components of the multi-root three-stage implant described in WO Pat. App. No. 2006/082610 into the osteotomy at the implant site, as there are further significant drawbacks in this method of preparation for receiving in the implant site the design of the multi-root components of this prior art, as well as the actual design form of the multi-root implant components described in this prior art.
WO Pat. No. 2006/082610 allows for the preparation and insertion of one and only one “head” stage form (component) in the implant site, and only for “multiple” rooted implants, a distinct disadvantage. This is due to the fact that this prior art describes only one template form that allows for the creation of bone preparation holes to accommodate this one particular “head” stage form (component).
A further major drawback of the entire prior art (including this particular prior art) is that they do not allow for surgical templates that allow for the placement of different mesio-distal length “heads”. The prior art does describe one other alternate shape (elliptical) for the “head” stage form (component) but provides no means for preparing the implant site to accommodate this other shape, a serious drawback of the prior art. Additionally, the cross-sectional shape of the particular “head” component described in this prior art for which it does provide a basic means for preparing the bone site to accommodate its form, does not conform to the natural cross-sectional form of any of the natural molars at the crestal height of the bone (the level of the implant-abutment interface, known in the dental field as the crucial “biological width” or attachment zone) and is therefore a poor choice of “head” form (component) from a biological perspective to implant into the posterior jawbones.
The above elements described may be critical requirements, as noted above, for the successful implantation of any dental implant and are actually more critical requirements for the successful placement by the dental practitioner and long term viability of a “multi-rooted” posterior (molar) implant due to the larger number of components (compared to a “single-rooted” anterior implant) which must accurately be related to each other and related to the bone preparation fashioned to receive them. Additionally, a posterior molar implant should be able to handle the significantly greater amount of load (stress forces) it must withstand due to its position and normal function requirements (holding up the bite and chewing forces).
U.S. Pat. App. No. US 2010/003635, January 2010, Feith, describes a “multi-root” implant based on a physical composition of zirconium oxide as opposed to the standard titanium or titanium alloy. This is based on a “one-piece” design of the entire implant (roots, and abutment). The multiple “roots” described are not threaded (screws), their “heads” are integral part of their “roots” and their center axes are parallel to each other to allow for a straight path of insertion.
In an attempt to provide for a more anatomically correct abutment form for posterior teeth (molars), U.S. Pat. App. No 2008/0293012, November 2008, de Resende Chaves and Martinez describe a splint abutment component for a single stage “root screw” form of a two stage dental implant. This design in fact results in a biomechanical disadvantage over the previous art as it embodies a wider platform (known in the dental implant field as platform switching) for occlussal loading (chewing) which then narrows to the standard round cross-sectional diameter of a standard “head” of a standard dental implant. This exaggerated platform switching design (compared to the other prior art) may actually lead to increased bone loss, known in the dental filed as “craterization” or “saucerization”, a well known deleterious consequence commonly found in the bone surrounding the “heads” of all the current prior art once the molar implants are placed under occlussal load for a sufficient period of time in the oral cavity. This “craterization” is due to the “overloading” of the “head” of the implant which caused the bone to die back or resorb.
Surgical Guide Clamps: U.S. Pat. App. No. US 2004/0013999, January 2004, Sussman, and U.S. Pat. App. No. US2009/0202959, August 2009, Ajlouni and Adjlouni, both describe a surgical guide clamp to be utilized to guide the bone drills in the preparation of the osteotomy at the implant site. U.S. Pat. App. No. US2004/0013999 describes a basic cylindrical ring form from which projects a horizontal cross-member. From this horizontal cross-member project, at right angles to it, two short bars with “teeth” on their inferior aspect to engage the vestibular regions of the jaw bone. This prior art offers no features to adjust the location of the guide ring in any of the three axes, nor does it take into account the adjacent teeth, which, based on its design dimensions, would interfere with its placement between the adjacent teeth in close proximity to the surface of the intended implant site. The guide ring of this prior art also only allows for the preparation of the standard round cross-sectional form for the entire length of the implant body (standard implant form).
U.S. Patent App. No. US 2009/0202959 is an advancement on the basic design of U.S. Pat. App. No. 2004/0013999, as it does allow for the accurate adjustment of its ring shaped guide form in three axes, and attaches with clamping members to the adjacent teeth on either side of the implant site. This design though, does not allow for the clamping of the device in the very common situation requiring dental implant restorations, of what is termed in the dental field as a “free-end saddle” case. This is a situation where there is a missing tooth or teeth space(s) behind (distal) to whatever is the terminal tooth in that arch or quadrant of teeth of the jawbones (upper and lower). Additionally, the design of this prior art does not contain a swiveling feature as does the present invention in order to rotate its ring guide in an off-axis manner relative to the width and length (bucco-lingual and mesio-distal) dimensions of the alveolar ridge at the proposed implant site. The guide ring of this prior art also only allows for the preparation of the standard round cross-sectional form for the entire length of the implant body (standard implant form).